An example of a classical trickle feed solar collector is the Thomason solar collector in which a corrugated galvanized roofing absorber is mounted between an upper glazing layer and a backing layer of insulating material. The galvanized roofing corrugated absorber is covered with an appropriate absorbing color such as black, and the corrugations are oriented down hill for trickle feeding the heat transfer fluid. The heat transfer fluid is dispensed along the top of the collector by a heat transfer fluid inlet manifold. Heated fluid is delivered at the base of the solar collector by a heat transfer fluid outlet manifold such as a gutter. Such conventional trickle feed solar collectors are constructed in a variety of configurations and combinations from a variety of materials.
A disadvantage of the conventional trickle feed solar collector configuration is that the relatively low absorber surface area to absorber volume ratio for the galvanized roofing corrugated absorber layer can result in relatively inefficient heat transfer to the heat transfer fluid. A greater shortcoming of the conventional trickle feed solar collector is that condensation and fog from the rivulets of water or other heat transfer fluid passing down the corrugation valleys forms on the inside surface of the upper glazing layer, dispersing sunlight and interfering in the solar collection and absorption by the surfaces of the absorber.
Another disadvantage of the traditional trickle feed solar collector structures is that they are generally constructed and available only in standard sizes and can be constructed in custom sizes only at substantial additional expense.